Apple Watch Series 3 comes in two models, one with GPS and cellular, and one with GPS, both featuring a 70 per cent faster dual-core processor and new wireless chip

Apple Watch will be available in case sizes of 38mm and 42mm from Sept 29Photo:PTI

Apple on Tuesday launched Apple Watch Series 3 with a built-in cellular to let users stay connected, make calls, receive texts and more, even if the iPhone is not nearby.

The third-generation Apple Watch is also a health and fitness companion with intelligent coaching features, water resistance 50 metres and a new barometric altimeter that measures relative elevation.

Apple Watch is available in two different case sizes, 38mm and 42mm from September 29 in India.

Apple Watch Series 3 (GPS + Cellular) will be available in gold, silver and space grey aluminium, or silver or space black stainless steel paired with a variety of bands.

Apple Watch Series 3 (GPS) will be available in gold, silver and space grey aluminium cases with a Sport Band starting at Rs 29,900.

Apple Watch Series 1 is available in silver or space grey aluminium cases paired with a Sport Band starting at Rs 21,900. Apple Watch Nike+ starts at Rs 29,900.

Apple Watch Series 3 comes in two models, one with GPS and cellular, and one with GPS, both featuring a 70 per cent faster dual-core processor and new wireless chip.

"We believe the addition of cellular will transform the way people use Apple Watch, providing a new sense of freedom since they can stay connected with or without their iPhone," Jeff Williams, Apple's Chief Operating Officer, said in a statement.

Apple Watch Series 3 (GPS + Cellular) features a full LTE cellular radio that switches seamlessly to cellular when it is away from iPhone. The watch shares the same number as iPhone so there's no need to provide an additional number to family, friends or colleagues.

Customers have the ability to make cellular calls directly with Apple Watch Series 3 (GPS + Cellular). The antenna design uses the display itself as both a transmitting and receiving element for LTE

The dual-core processor in the device allows for quicker app launch times, smoother graphics and enables Siri to speak using the built-in speaker.

Apple designed a new custom wireless chip called W2, making Wi-Fi 85 per cent faster and Bluetooth and Wi-Fi 50 per cent more power efficient.

watchOS 4 features an updated Heart Rate app, giving even more insight to heart rate, including measurements during resting, workout, recovery, walking and Breathe sessions.

The redesigned Music app experience automatically synchronises playlists like New Music Mix and Favourites Mix, along with the user's most listened to music.